Fluorinated, saturated hydrocarbons

ABSTRACT

A composition containing less than 95 mol % of a trihydrofluorinated saturated hydrocarbon represented by the following formula (I) 
     
       
         Rf 1 —R 1 —Rf 2   (I) 
       
     
     (wherein R 1  represents a carbon chain in which CHF and CH 2  are bound, and Rf 1  and Rf 2  are bound to each other to form a ring by a perfluoroalkylene chain of 2 to 4 carbon atoms) and the balance of a tetrahydrofluorinated saturated hydrocarbon having the same carbon number and the same carbon structure as the trihydrofluorinated saturated hydrocarbon, as represented by the following formula (II) 
     
       
         Rf 1 —R 2 —Rf 2   (II) 
       
     
     (wherein R 2  represents a carbon chain in which CH 2  and CH 3  are bound, and Rf 1  and Rf 2  are as defined above) is provided as a composition containing, in a high proportion, trihydrofluorocarbon, a hydrofluorocarbon (HFC) known to have a small global heating coefficient, which has less influence on the global environment, shows less toxicity to animals, and is chemically stable.

This application is a 371 application of PCT/JP98/02157 filed May 15,1998.

1. Technical Field

The invention of this application relates to fluorinated saturatedhydrocarbons. More specifically, the invention of this applicationrelates to fluorinated saturated hydrocarbons, which are useful assubstitute compounds of CFC (chlorofluorocarbon), HCFC(hydrochlorofluorocarbon), PFC (perfluoro compound), and chlorine-typesolvents, which have been widely used as detergents, foaming agents,refrigerants, and the like. The compounds described in the invention ofthis application have less influence on the global environment, showless toxicity to human bodies, and are chemically stable. The inventionof this application also relates to a process for producing the abovecompounds, and compositions thereof.

2. Background of the Invention

As an industrial method for washing various materials, products composedmainly of CFC 113 or 1,1,1-trichloroethane which are incombustible, lowin toxicity, and excellent in stability have been widely used. However,it has been identified that various CFCs, 1,1,1-trichloroethane, carbontetrachloride and the like destroy the stratospheric ozone layer. Inview of the protection of the ozone layer, the production of CFC 113,1,1,1-trichloroethane and the like has been completely abolishedworldwide since the end of 1995, and regulations have been set on theiruse.

As substitutes of CFC 113 and the like, hydrochlorofluorocarbons such asHCFC 225 and HCFC 141b have been proposed. However, since thesecompounds are, though slightly, also destructive to the ozone layer, atime limit has been set in their use. Further, chlorinated solvents suchas methylene chloride, trichloroethylene, perchloroethylene and the likehave also been problematic regarding their safety (carcinogenicity andintoxication), and various regulations have been already set or arebeing studied.

Further, various fluorine type compounds which do not contain chlorineatoms that cause the destruction of the ozone layer, and can maintainnon-combustibility, safety and such merits as mentioned above, have beensynthesized. For example, a product composed mainly of perfluorocarbonssuch as perfluoro-n-heptane (WO 92-03205 and the like), a productcomposed mainly of acyclic hydrofluorocarbon (WO 95-06693, JP-W-6-501949and the like), a product composed mainly of specific acyclichydrofluorocarbons (WO 95-05448) and the like are mentioned.

These perfluorocarbons and hydrofluorocarbons were preferable becausethere is no worry for the destruction of the ozone layer and detergencywith good finish is exhibited by using the same as such or along withorganic solvents. However, these compounds each had problems that neededto be improved. For example, perfluorocarbons have high global warmingcoefficient, and there is fear that new problems on the preservation ofthe global environment might occur. Further, with respect to acyclic orcyclic hydrofluorocarbons, various structures have been proposed, buthave problems in their structures. For example, compounds having—CH₂CH₂— bonds, with 4 or 5 carbon atoms, and a boiling point in theregion suitable for detergents or solvents, are combustible.

Accordingly, an object of the invention of this application is toprovide, upon improving the defects of such hydrofluorocarbons known sofar, fluorinated saturated hydrocarbons which are excellent asdetergents, and excellent in their non-combustibility and theirstability in the presence of water, which can construct now detergentsand the like, and are easy to produce, a process for producing the same,and compositions thereof.

DISCLOSURE OF THE INVENTION

The invention of this application is to provide, as a product to solvethe above-mentioned problems, a composition comprising less than 95 mol% of a trihydrofluorinated saturated hydrocarbon (A) represented by thefollowing formula (I)

Rf₁—R₁—Rf₂  (I)

(wherein R₁ represents a carbon chain in which CHF and CH₂ are bound,and Rf₁ and Rf₂ are bound to each other to form a ring by aperfluoroalkylene chain of 2 to 4 carbon atoms)

and the balance of a tetrahydrofluorinated saturated hydrocarbon (B)having the same number of carbons and the same carbon structure as thetrihydrofluorinated saturated hydrocarbon (A), as represented by thefollowing formula (II)

Rf₁—R₂—Rf₂  (II)

(wherein R₂ represents a carbon chain in which CH₂ and CH₂ are bound,and Rf₁ and Rf₂ are as defined above).

The reason that the proportions of the fluorinated saturatedhydrocarbons (A) and (B) are as mentioned above is that according to theinvention of this application, the fluorinated hydrocarbon of thisinvention is provided by a specific process described later in thisapplication, and as a content of a detergent or the like, thefluorinated saturated hydrocarbon of this invention is introduced as anovel product.

The proportion of the trihydrofluorinated hydrocarbon (A) is less than95 mol %, generally 10 mol % or more, preferably 50 mol % or more, morepreferably 70 mol % or more, further preferably 80 mol % or more. Thehigher the proportion of the trihydrofluorinated hydrocarbon (A), themore the fluorinated saturated hydrocarbon of this invention becomesnon-combustible.

The fluorinated saturated hydrocarbons (A) and (B) are cyclic. Thenumber of carbon atoms in the fluorinated hydrocarbons is between 4 and6, and most preferably 5. Specific compounds of the fluorinatedsaturated hydrocarbon (A) having the trihydrofluorocarbon chain include1,1,2,2,3-pentafluorocyclobutane, 1,1,2,2,3,3,4-heptafluorocyclopentane,and 1,1,2,2,3,3,4,4,5-nonafluorocyclohexane, of which1,1,2,2,3,3,4-heptafluorocyclopentane (HFCPA) is mentioned as especiallypreferable.

In this invention, the tetrahydrofluorinated saturated hydrocarbon (B)having the same number of carbons and the same carbon structure as thetrihydrofluorinated saturated hydrocarbon (A) co-exists. For example, itis shown that 1,1,2,2,3,3-hexafluorocyclopentane co-exists with1,1,2,2,3,3,4-heptafluorocyclopentane (HFCPA) mentioned above.

The composition of this invention is excellent in detergency, is highlynon-combustible, is excellent in stability under the presence of water,and the production thereof is easy.

Thus, the process for producing the composition of the invention of thisapplication is described.

The process for producing the composition of this invention, whichcontains the fluorinated hydrocarbon compounds represented by formulas(III) and (IV) such as the fluorinated hydrocarbons (A) and (B)mentioned above, is quite unique. For example, the formation of1H,1H,2H-heptafluorocyclopentane or the like which is a trihydrocompound has been so far observed during the reaction of hydrogenatingperfluorocyclopentene in the presence of palladium-alumina, and it isdisclosed that the main product of this reaction is1H,2H-octafluorocyclopentane (J. Chem. Soc., C.548 (1968)). Only 10% ofheptafluorocyclopentane (HFCPA) having a trihydrofluorocarbon chain wasreportedly obtained, and further, was difficult to separate fromoctafluorocyclopentane (OFCPA) by distillation.

Moreover, according to the official gazette of JP-B-5-148171, when1,1,1,2,2,3,4,5,5,5-decafluoropentane is produced by hydrogenatingdecafluoropentene-2 using palladium supported on carbon, alumina, or thelike as a catalyst, by products such as1,1,1,2,2,4,5,5,5-nonafluoropentane,1,1,1,2,2,3,5,5,5-nonafluoropentane, 1,1,1,2,2,5,5,5-octafluoropentaneand the like were produced in large amounts. However, it was reportedlydifficult to separate these by-products from the desired product by theprocess of distillation.

That is, providing fluorinated saturated hydrocarbons containingheptafluorocyclopentane (HFCPA) and the like which containtrihydrofluorocarbon chains in high proportions has not beenindustrially realized so far.

Meanwhile, in the process of this invention, a cyclic fluorinated,unsaturated hydrocarbon having the unsaturated fluorocarbon chain asrepresented by formula (V) is used as a substrate starting material, andis catalytically reduced in a hydrogen atmosphere using a noble metalcatalyst. Here, the proportions of the fluorinated saturated hydrocarbonof formula (III) and the fluorinated saturated hydrocarbon of formula(IV) are controlled by changing the polarity of the component in thereaction system, other than the substrate starting material.

That is, in the method of this invention, the fluorinated saturatedhydrocarbon of formula (III) can be produced more selectively by makingthe polarity of the component other than the substrate starting materialof the reaction system high. On the other hand, the fluorinatedsaturated hydrocarbon of formula (IV) can be produced more selectivelyby making the polarity of the component other than the substratestarting material of the reaction system low. For example, when anunsaturated fluorinated hydrocarbon having carbon chains of —CF═CF—, asin formula (V), is the starting material, where the symbol X representsa fluorine atom (F), a trihydrofluorinated saturated hydrocarbon havinga carbon chain of —CHF—CH₂— as the fluorinated saturated hydrocarbon offormula (III) can be produced by making the polarity of the componentother than the substrate starting material of the reaction system high.Meanwhile, when an unsaturated, fluorinated hydrocarbon having a carbonchain of —CH═CF— in which the symbol X in formula (V) represents ahydrogen atom (H) is used as a starting material, a trihydrofluorinatedsaturated hydrocarbon having a carbon chain of —CHF—CH₂— as thefluorinated saturated hydrocarbon of formula (IV) can selectively beproduced by making the polarity of the component other than thesubstrate starting material of the reaction system low.

In the fluorinated, unsaturated hydrocarbon represented by formula (V)as the substrate starting material, the carbon number is between 4 and6, most preferably 5. Further, the fluorinated, unsaturated hydrocarbonis cyclic. The starting material can be obtained depending on variousmethods and the like. For example, the synthesis thereof can beconducted by a method described in the official gazette of JP-A-8-12608or the like.

Here, the component other than the substrate starting material of thereaction system refers to high-polarity compounds or low-polaritycompounds added to the substrate starting material, or impuritiesaccompanying the substrate starting material.

That is, in order to make the polarity of the component other than thesubstrate starting material of the reaction system high, it is advisableto use, for example, a starting material containing the fluorinated,unsaturated hydrocarbon represented by formula (V) as the substratestarting material, and a high-polarity compound or a starting materialobtained by removing the low-polarity compounds from the impuritiesaccompanying the substrate starting material to increase the proportionof the high-polarity compounds in impurities. Further, in order to makethe polarity of the component other than the substrate starting materialof the reaction system low, it is advisable to use, for example, astarting material containing the fluorinated, unsaturated hydrocarbonrepresented by formula (V) and a low-polarity compound or a startingmaterial obtained by removing the high-polarity compounds fromimpurities accompanying the substrate starting material to increase theproportion of the low-polarity compound in impurities. Here, thepolarity of the compound used can be defined by a dielectric constant asdescribed in, for example, Organic Solvents (John A. Riddick, et al(1986), John Wiley & Sons, Inc. 4th Edition), Kagaku Binran (Kisohen II,II-498 to II-501) or the like.

Accordingly, a process in which a trihydrofluorinated saturatedhydrocarbon in which the symbol X of formula (III) represents a fluorineatom, is selectively produced by making the polarity of the componentother than the substrate starting material of the reaction system high,is first described.

In this case, a compound in which the symbol X in formula (V) representsa fluorine atom is used as a starting material. Specific examplesthereof include, for example, cyclic fluorinated, unsaturatedhydrocarbons such as 1,1,2,2,3,4-hexafluorocyclobutene,1,1,2,2,3,3,4,5-octafluorocyclopentene,1,1,2,2,3,3,4,4,5,6-decafluorocyclohexene and the like; and so forth. Ofthese, 1,1,2,2,3,3,4,5-octafluorocyclopentene is mentioned especiallypreferably.

The low-polarity compound of which the amount has to be adjusted to asmall amount relative to the substrate, in order to make the polarity ofthe component other than the substrate starting material of the reactionsystem high includes, for example, paraffins such as n-pentane,n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-undecane,n-dodecane, n-tridecane, n-tetradecane, n-pentadecane and the like, andstructural isomers thereof; naphthenes such as cyclopentane,cyclohexane, methylcyclohexane and the like; aromatics such as benzene,toluene, o-xylene, m-xylone, p-xylene and the like, and analoguesthereof; mineral oils such as a machine oil, a cutting oil, a printingink oil, a vacuum pump oil and the like; chlorofluorocarbons such aschlorononafluorocyclopentane, chloroheptafluorocyclopentene and thelike; and so forth. The content of these low-polarity compounds is 1% byweight or less, preferably 0.5% by weight or less, more preferably 0.1%by weight or less.

The low-polarity compound to be noted especially is paraffins,naphthenes and aromatics.

The low-polarity compound accompanying the substrate starting materialcan reduce the content in the starting material by means such asadsorption treatment using an adsorbent and the like. For example, thetreatment with an adsorbent such as an activated carbon or the like is atypical one.

And in the process of this invention, it is also important that thesubstrate starting material is mixed with the high-polarity compound. Asthe high-polarity compound, there are water, alcohols, polyhydricalcohols, monoethers of these polyhydric alcohols, amides, sulfoxidesand the like. Specific examples include, for example, alcohols such asmethyl alcohol, ethyl alcohol, n-propyl alcohol, n-butyl alcohol,n-pentyl alcohol and the like, and their structural isomers; polyhydricalcohols such as ethylene glycol, glycerol, diethylene glycol,diethylene glycol monomethyl ether and the like, and monoethers of thesepolyhydric alcohols; amides such as N,N-dimethylacetamide,N,N-dimethylformamide and the like; sulfoxides such as dimethylsulfoxide and the like; and so forth. The mixing proportion of thesehigh-polarity compounds is not particularly limited, and they may beused as additives or solvents. Further, these high-polarity compoundsmay be used either alone or in mixtures of two or more.

Usually, the mixing proportion is between 0.1 and 20% by weight based onthe substrate starting material. It is preferably between 0.1 and 15% byweight, more preferably between 0.5 and 15% by weight.

Next, a process for producing the fluorinated saturated hydrocarbon offormula (IV) more selectively by making the polarity of the componentother than the substrate starting material of the reaction system low isdescribed.

In this case, it is important that the low-polarity compound iscontained in the starting material. Examples of the low-polaritycompound are the same as the above-mentioned. It is advisable that theproportion of these low-polarity compounds is between 0.1 and 20% byweight. It is preferably between 0.1 and 15% by weight, more preferablybetween 0.5 and 15% by weight. Further, these low-polarity compounds maybe used either alone or in admixture of two or more.

Further, in this invention, it is also important to reduce the contentof the high-polarity impurities relative to the starting material.Examples of the high-polarity compound are the same as theabove-mentioned. The content of these high-polarity impurities has to be1% by weight or less in the starting material. It is preferably 0.5% byweight or less, more preferably 0.1% by weight or less.

With respect to the high-polarity compound accompanying the substratestarting material, the content in the starting material can be decreasedby means such as adsorption treatment using an adsorbent or the like.For example, treatment with an adsorbent such as activated alumina orthe like is a typical one.

The trihydrofluorinated saturated hydrocarbon in which the symbol X informula represents a hydrogen atom is selectively produced as thefluorinated saturated hydrocarbon of formula (IV) by making low thecomponent other than the substrate starting material of the reactionsystem. In this case, the starting material is a compound represented bythe formula (V), in which X is a hydrogen atom. Examples include cyclicfluorinated, unsaturated hydrocarbons such as1,1,2,2,3-pentafluorocyclobutene, 1,1,2,2,3,3,4-heptafluorocyclopenteneand the like. Of these, 1,1,2,2,3,3,4-heptafluorocyclopentene ismentioned especially preferably.

The fluorinated saturated hydrocarbon containing the trihydrofluorinatedhydrocarbon (A) and the tetrahydrofluorinated saturated hydrocarbon (B)in this invention corresponds to the case in which the fluorinatedunsaturated hydrocarbon of the following formula where the symbol Xrepresents a hydrogen atom, is used as the starting compound of formula(V), as mentioned above.

Rf₁—CH═CF—Rf₂

The trihydrofluorinated saturated hydrocarbon (A) can be controlled to aproportion of less than 95 mol % while co-existing with thetetrahydrofluorinated saturated hydrocarbon (B).

As the noble metal catalyst in the process of this invention, a noblemetal supported on a carrier is usually used. The noble metal mentionedhere refer to palladium, rhodium, ruthenium, rhenium and platinum.Palladium, rhodium and ruthenium are most preferable. These metals maybe used either alone or as an alloy of two or more metals, a so-calledbimetal catalyst. The type, shape and size of the carrier are notparticularly limited. Activated carbon, alumina and titania arepreferable. They may be powders, or molded products such as spheres andpellets. The amount of the noble metal supported on the carrier isbetween 0.5 and 20% by weight. It is recommendable that the amountsupported is between 1 and 20% by weight in powder and between 1 and 10%by weight in molded products. More preferably, a catalyst powder havingthe amount supported of from 1 to 10% by weight is recommended.

The reaction pressure is not particularly limited. A pressure in therange of atmospheric pressure to 10 kgf/cm² is recommended. The reactiontemperature is not particularly limited, either. A temperature in therange of ordinary temperature to 350° C. is recommended. Further, thereaction, may be conducted in a liquid phase, or a gaseous phase, asrequired.

After the completion of the reaction, as a post-treatment, purificationmay be conducted by filtering the catalyst, neutralizing and washing theresulting filtrate and conducting distillation. For example, whenoctafluorocyclopentene (OFCPE) is hydrogenated by the process of thisinvention, hexafluorocyclopentane can be formed. The boiling point ofthis compound is between 87 and 88° C. at atmospheric pressure, whilethe boiling point of heptafluorocyclopentane (HFCPA) is 80° C. atatmospheric pressure, and the boiling point of octafluorocyclopentane(OFCPA) is 79° C. at atmospheric pressure. Accordingly, they can easilybe separated through distillation.

When the fluorinated saturated hydrocarbons (A) and (B) are used in asolvent composition constituting a detergent, the proportion of thefluorinated saturated hydrocarbon (A) having the trihydrofluorocarbonchain usually exceeds 10%, and is preferably 50% by weight or more, morepreferably 70% or more, most preferably 80% or more. This is because asthe proportion of the trihydrofluorinated saturated hydrocarbon (A) isincreased, the non-combustibility of the fluorinated saturatedhydrocarbon increase.

In case of constituting the composition, it is effective to contain atleast one organic solvent having a boiling point of at least 25° C. andat most 250° C. to increase the solubility of contaminants such as oils,flux, waxes and the like. The amount of these organic solvents added isnot particularly limited, but is usually 50% by weight or less,preferably between 2 and 30% by weight, more preferably between 3 and20% by weight based on the total amount. When the organic solvent formsan azeotropic composition, use in the region of the azeotropiccomposition is preferable.

The type of such an organic solvent is not particularly limited. Forexample, at least one organic solvent selected from hydrocarbons,alcohols, esters, chlorinated hydrocarbons, other fluorinatedhydrocarbons, others, ketones and volatile organic silicones may beused.

The hydrocarbons mentioned above, are not particularly limited. Forexample, aliphatic hydrocarbons such as n-pentane, n-hexane, n-heptane,isohexane, isoheptane, n-octane, isooctane, n-decane, isodecane,n-undecane, n-dodecane, n-tridecane and the like, alicyclic hydrocarbonssuch as cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexaneand the like, and aromatic hydrocarbons such as benzene, toluene, xyleneand the like can be selected.

The alcohols mentioned above are not particularly limited either. Forexample, methanol, ethanol, isopropanol, n-propanol, n-butanol,s-butanol, t-butanol, n-pentanol, isopentanol, n-hexanol, isohexanol,2-ethylhexanol, n-octanol and the like are mentioned. Of these, thosehaving 5 or less carbon atoms are preferable, and those having 1 to 4carbon atoms are especially preferable.

The esters mentioned above are not particularly limited either. Forexample, methyl acetate, ethyl acetate, propyl acetate, isopropylacetate, butyl acetate, isobutyl acetate, pentyl acetate, methylpropionate, ethyl propionate, propyl propionate, isopropyl propionate,methyl butyrate, ethyl butyrate, isopropyl butyrate, methyl valerate,ethyl valerate and the like are mentioned. Of these, those having 3 to10 carbon atoms are preferable, and those having 3 to 6 carbon atoms areespecially preferable.

The chlorinated hydrocarbons mentioned above are not particularlylimited. For example, methylene chloride, dichloroethane,dichloroethylene, trichloroethylene, perchloroethylene and the like arementioned.

The fluorinated hydrocarbons mentioned above are not particularlylimited, and may be mainly composed of carbon, hydrogen and fluorine andcontain oxygen atoms or unsaturated bonds. Of these, those havingboiling points of 25° C. or more are preferable. As such fluorinatedhydrocarbons, for example, pentafluoropropane, hexafluorobutane,decafluoropentane, hexafluorocyclopentane, octafluorocyclopentane,perfluoropropylmethyl ether, perfluorobutylmethyl ether,perfluorobutylethyl ether, hexafluorocyclopentane,heptafluorocyclopentane, octafluorocyclopentene and the like can beused. Further, hexafluorocyclopentane, octafluorocyclopentane,hexafluorocyclopentene and the like having cyclic structures and theappropriate boiling points are preferable.

The ketones mentioned above are not particularly limited. For example,acetone, 2-butanone, 2-pentanone, 3-pentanone, 2-hexanone,3-methyl-2-butanone, cyclopentanone, cyclohexanone,2-methyloyclopentanone, 2-methylcyclohexanone and the like may beselected.

As the volatile organosilicones mentioned above, hexamethyldisiloxane,octamethyltrisiloxane, decamethyltetrasiloxane,hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane,decamethylcyclopentasiloxane and the like are mentioned.

Further, various additives known so far may be added to the detergent ofthis invention. As additives, there are, for example, stabilizers,surfactants and the like. As the stabilizer, aliphatic nitro compoundssuch as nitromethane, nitroethane and the like, acetylene alcohols suchas 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol and the like, epoxidessuch as glycidol, methylglycidyl ether, acrylglycidyl ether and thelike, ethers such as dimethoxymethane, 1,4-dioxane and the like,unsaturated hydrocarbons such as hexene, heptene, cyclopentene,cyclohexene and the like, unsaturated alcohols such as allyl alcohol,1-buten-3-ol and the like, acrylates such as methyl acrylate, ethylacrylate and the like, and so forth are mentioned.

Further, as the surfactant, anionic surfactants, cationic surfactants,nonionic surfactants, and amphoteric surfactants known so far may beused. As the anionic surfactant, for example, a carboxylate, asulfonate, a sulfate, a phosphate and the like may be used. As thecationic surfactant, for example, salts of amines and various acids andquaternary ammonium salts are mentioned. As the nonionic surfactant, forexample, polyoxyethylene ether, polyoxyethylene-polyoxypropylene glycol,polyoxyethylone-polyoxypropylene alkyl ether, polyhydric alcoholaliphatic acid partial ester and the like are mentioned. As theamphoteric surfactant, for example, betaines, organic amino acids, aminesalts of fatty acids and the like are mentioned. Further, surfactantscontaining fluorine atoms are also preferable. When these surfactantsare added, it is possible to effectively remove and dry the wateradhered to processed parts of metals, ceramics, glasses, plastics,elastomers and the like, after water-washing. The amount of thesurfactant is not particularly limited. It is usually 30% by weight orless, preferably 20% by weight or less, more preferably between 0.005and 10% by weight based on the total amount.

The products to be washed are not particularly limited either. Forexample, metals, ceramics, glasses, plastics, elastomers and the likeused in industries such as the precision machinery industry, the metalprocessing industry, the optical machinery industry, the electronicindustry, and plastics industry may be washed with the product of thisinvention. Specifically, a wide variety of products such as automobileparts, as in bumpers, gears, mission parts, and radiator parts,electronic and electric parts such as printed circuit boards, IC parts,lead frames, motor parts, and condensers, precision machine parts suchas bearings, gears, engineering plastics gears, watch parts, cameraparts, optical lenses and such, large-sized machine parts such asprinters, printer blades, printing rolls, flat rolled products, buildingmachines, glass substrates, and large-sized heavy machine parts,household products such as tableware, and fiber products may bementioned as examples.

The types of the contaminants, removed by product of the presentinvention, may be oils such as cutting oils, quenching oils, rollingoils, lubricants, machine oils, press oils, blanking oils, drawing oils,assembling oils, and wire drawing oils, as well as greases, waxes,adhesives, fats and oils, release agents in molding, thumb-marks, fluxafter soldering, resists, and solder pastes.

With respect to the washing method, the product to be washed may bewashed by its contact with the washing solvent composition, usingregular washing methods. Specifically, methods such as hand wiping,dipping, spraying, showering or the like may be applied. In thesetreatments, physical means such as ultrasonic vibration, shaking,stirring, brushing or the like may be used in combination.

In the washing process, an organic solvent made of at least one typeselected from aliphatic hydrocarbons, alicyclic hydrocarbons, aromatichydrocarbons, alcohols, esters, chlorinated hydrocarbons, ethers,ketones and volatile organosilicones may also be used as a solvent otherthan the detergent of the present invention.

In such a case, a method comprising two steps, a step of removingcontaminants of the product to be washed and a step of rinsing anorganic solvent adhered to the product after the removal of contaminantsby contacting the same with the detergent of this invention orvapor-cleaning the same in a vapor of a detergent (so-called co-solventsystem), is employed.

On the basis of the foregoing, preferred modes for carrying out thisinvention are summed up below.

1. The number of carbon atoms in the trihydrofluorinated saturatedhydrocarbon (A) is 5.

2. The trihydrofluorinated saturated hydrocarbon is1,1,2,2,3,3,4-heptafluorocyclopentane.

3. The fluorinated saturated hydrocarbon of formula (III) is selevtivelyproduced through catalytic reduction by making the component other thanthe substrate starting material of the reaction system to have a highpolarity.

4. In the above-mentioned 3, the catalytic reduction is conductd using astarting material in which the proportion of the high-polarity compoundin the impurities is increased by adding a high-polarity compound in thefluorinated unsaturated hydrocarbon represented by formula (V) used asthe substrate starting material, or by removing the low-polaritycompound from the impurities accompanying the substrate startingmaterial.

5. The fluorinated saturated hydrocarbon of formula (IV) is selectivelyproduced through catalytic reduction by making the component other thanthe substrate starting material of the reaction system have a lowpolarity.

6. In the above-mentioned 5, the catalytic reduction is conducted usinga starting material in which the proportion of the low-polarity compoundin the impurities is increased by adding a low-polarity compound in thefluorinated unsaturated hydrocarbon represented by formula (V) used asthe substrate starting material, or by removing the high-polaritycompound from the impurities in the substrate starting material.

7. In the above-mentioned 4, the low-polarity compound is added to thestarting material in an amount of 0.5% by weight or less.

8. In the above-mentioned 4, the high-polarity compound is contained inthe starting material in an amount of 0.1 to 15% by weight.

9. In the above-mentioned 6, the high-polarity compound is added to thestarting material in an amount of 0.5% by weight.

10. In the above-mentioned 6, the low-polarity compound is added to thestarting material in an amount of 0.1 to 15% by weight.

11. In the above-mentioned 4 or 6, the low-polarity compound is aparaffin, napthene or aromatic compound.

12. In the above-mentioned 4 or 6, the high-polarity compound is analcohol, a polyhydric alcohol, a polyhydric alcohol monoether, an amide,or a sulfoxide.

13. In the above-mentioned 4, the low-polarity compound accompanying thesubstrate starting material reduces the content in the starting materialby adsorption treatment with an absorbent.

14. In the above-mentioned 6, the high-polarity compound accompanyingthe substrate starting material reduces the content in the startingmaterial by adsorption treatment with an adsorbent.

15. In the above-mentioned 3, a trihydrofluorinated saturatedhydrocarbon of formula (III) is selectively produced by using afluorinated unsaturated hydrocarbon having carbon chains of —CF═CF— asin formula (V) as the starting material, in which the symbol Xrepresents a fluorine atom.

16. In the above-mentioned 5, a trihydrofluorinated saturatedhydrocarbon of formula (IV) is selectively produced by using afluorinated, unsaturated hydrocarbon having a carbon chain of —CH═CF— asin formula (V) as the starting material, in which the symbol Xrepresents a hydrogen atom.

17. The fluorinated, unsaturated hydrocarbon of formula (V) as thestarting material in the above-mentioned 3 or 5 has 5 carbon atoms.

18. The fluorinated, unsaturated hydrocarbon used as the startingmaterial in the abve-mentioned 15 is1,1,2,2,3,3,4,5-octafluorocyclopentene.

19. The fluorinated, unsaturated hydrocarbon used as the startingmaterial in the above-mentioned 16 is1,1,2,2,3,3,4-heptafluorocyclopentene.

20. In the above-mentioned 3 or 5, the catalytic reduction is conductedunder hydrogen in the presence of a noble metal catalyst.

21. In the above-mentioned 20, the noble metal is palladium, rhodium,ruthenium, rhenium or platinum.

22. In the above-mentioned 21, the noble metal is palladium, rhodium orruthenium.

23. In the above-mentioned 20, the noble metal catalyst is one in whichthe noble metal is contained in a carrier.

24. In the above-mentioned 23, the carrier is activated carbon, aluminaor titania.

25. In the above-mentioned 23, the amount of metal contained in thecarrier is between 0.5 and 20% by weight.

26. In the above-mentioned 20, the catalytic reduction is conducted as aliquid phase reaction or a gaseous phase reaction at a pressure in therange of atmospheric pressure to 10 kg/cm², in a hydrogen atmosphere,and a temperature in the range of ordinary temperature to 350° C.

27. In a composition containing the fluorinated saturated hydrocarbons(A) and (B), the proportion of the trihydrofluorinated saturatedhydrocarbon (A) exceeds 10 mol %.

28. In the above-mentioned 27, it is 50 mol % or more.

29. In the above-mentioned 28, it is 70 mol % or more.

30. In the above-mentioned 29, it is 80 mol % or more.

31. In the above-mentioned 27, an organic solvent having a boiling pointof at least 25° C. and at most 250° C., is 50% or less by weight of thetotal amount.

32. In the above-mentioned 31, it is between 2 and 30% by weight.

33. In the above-mentioned 32, it is between 3 and 20% by weight.

34. In the above-mentioned 31, the organic solvent is a hydrocarbon, analcohol, an ester, a chlorinated hydrocarbon, a fluorinated hydrocarbon,an ether, a ketone or a volatile organosilicone.

The mode for carrying out this invention is illustrated morespecifically by referring to the following Examples.

EXAMPLE 1

One percent by weight of n-tridecane (dielectric constant 2.0), alow-polarity compound, was dissolved in crude1,3,3,4,4,5,5-heptafluorocyclopentene having a purity of 99.9 GC %. Anautoclave having a capacity of 100 ml was charged with a catalyst ofactivated carbon having supported thereon 5% by weight of powderedpalladium. After the deaeration under reduced pressure,n-tridecane-containing 1,3,3,4,4,5,5-heptafluorocyclopentene preparedpreviously was poured. While the mixture was stirred at 40° C., thereaction was conducted by repeating block charge of hydrogen at a gaugepressure in the range of 0 to 6 kgf/cm². After the completion of thereaction, the product was analyzed through gas chromatography.Consequently, a fluorinated saturated hydrocarbon containing 94 mol % of1,1,2,2,3,3,4-heptafluorocyclopentane (HFCPA) and 6 mol % of1,1,2,2,3,3-hexafluorocyclopentane was obtained.

EXAMPLE 2

The reaction was conducted as in the above-mentioned Example 1 withoutadding n-tridecane. Consequently, a product containing 70 mol % of1,1,2,2,3,3,4-heptafluorocyclopentane and 30 mol % of1,1,2,2,3,3-hexafluorocyclopentane was obtained.

EXAMPLE 3

Activated carbon as a typical nonionic adsorbent was charged into crudeoctafluorocyclopentene containing low-polarity hydrocarbon impuritiesand having a purity of 99 GC %. These were stirred, and filtered toremove the low-polarity compound from the impurities of the crudestarting material. Octafluorocyclopentene having a purity of 99.9 GC %in which the proportion of the high-polarity compound in the impuritywas increased was obtained. Then, an autoclave having a capacity of 100ml was charged with a catalyst of activated carbon having supportedthereon 5% by weight of palladium powder. After the deaeration underreduced pressure, octafluorocyclopentene (dielectric constant: 2.6)having a purity of 99.9% as prepared previously was poured in. While themixture was stirred at 40° C., the reaction was conducted by repeatingblock charge of hydrogen at a gauge pressure in the range of 0 to 6kgf/cm². After the completion of the reaction, the product was analyzedthrough gas chromatography. Consequently, a fluorinated saturatedhydrocarbon containing 75 mol % of heptafluorocyclopentane (HFCPA) and25 mol % of octafluorocyclopentane (OFCPA) was obtained.

EXAMPLE 4

Crude octafluorocyclopentene having a purity of 99 GC % was mixed withthe same volume of diethylene glycol monomethyl ether as a high-polaritycompound. An autoclave having a capacity of 100 ml was charged with acatalyst of activated carbon having supported thereon 5% by weight ofpalladium powder. After the deaeration under reduced pressure, themixture of octafluorocyclopentene and diethylene glycol monomethyl etherprepared previously was poured. While the resulting mixture was stirredat 40° C., the reaction was conducted by repeating block charge ofhydrogen at a gauge pressure in the range of 0 to 6 kgf/cm². After thecompletion of the reaction, the product was analyzed through gaschromatography. Consequently, a fluorinated saturated hydrocarboncontaining 85 mol % of heptafluorocyclopentane (HFCPA) and 15 mol % ofoctafluorocyclopentane (OFCPA) was obtained.

EXAMPLE 5

One percent by weight of n-tridecane (dielectric constant 2.0), alow-polarity compound, was dissolved in crude octafluorocyclopentenehaving a purity of 99.9 GC %. An autoclave having a capacity of 100 mlwas charged with a catalyst of activated carbon containing 5% by weightof palladium powder. After deaeration under reducedpressure,—tridecane-containing octafluorocyclopentene preparedpreviously was poured in. While the mixture was stirred at 40° C., thereaction was conducted by repeating the block charge of hydrogen at agauge pressure in the range of 0 to 6 kgf/cm². The product obtained wasanalyzed through gas chromatography. Consequently, a fluorinatedsaturated hydrocarbon containing 83 mol % of octafluorocyclopentane(OFCPA) and 17 mol % of heptafluorocyclopentane (HFCPA) was obtained.

EXAMPLE 6

n-Tridecane (3% by weight), a low-polarity compound was dissolved incrude octafluorocyclopentene having a purity of 99.9 GC %. An autoclavehaving a capacity of 100 ml was charged with a catalyst of activatedcarbon having supported thereon 5% by weight of palladium powder. Afterthe deaeration under reduced pressure, n-tridecane-containingoctafluorocyclopentene prepared previously was poured in. While themixture was stirred at 40° C., the reaction was conducted by repeatingblock charge of hydrogen at a gauge pressure in the range of 0 to 6kgf/cm². After the completion of the reaction, the product was analyzedthrough gas chromatography. Consequently, a fluorinated saturatedhydrocarbon containing 86 mol % of octafluorocyclopentane (OFCPA) and 14mol % of heptafluorocyclopentane (HFCPA) was obtained.

EXAMPLE 7

One percent by weight of o-xylene (dielectric constant 2.6), alow-polarity compound was dissolved in crude octafluorocyclopentenehaving a purity of 99.9 GC %. An autoclave having a capacity of 100 mlwas charged with a catalyst of activated carbon having containing 5% byweight of palladium powder. After the deaeration under reduced pressure,o-xylene-containing octafluorocyclopentene prepared previously waspoured. While the mixture was stirred at 40° C., the reaction wasconducted by repeating block charge of hydrogen at a gauge pressure inthe range of 0 to 6 kgf/cm². After the completion of the reaction, theproduct was analyzed through gas chromatography. Consequently, afluorinated saturated hydrocarbon containing 87 mol % ofoctafluorocyclopentane (OFCPA) and 13 mol % of heptafluorocyclopentane(HFCPA) was obtained.

EXAMPLE 8

Activated alumina as a typical ionic adsorbent was charged into crudeoctafluorocyclopentene having a purity of 99 GC %. These were stirred,and filtered to remove the high-polarity impurity from the impurities ofthe crude starting material. Octafluorocyclopentene having a purity of99.5 GC % in which the proportion of the low-polarity compound, in theimpurities was increased, was obtained. An autoclave having a capacityof 100 ml was charged with a catalyst of activated carbon havingsupported thereon 5% by weight of palladium as a powder. After thedeaeration under reduced pressure, octafluorocyclopentene having apurity of 99.5% as obtained previously was poured. While the mixture wasstirred at 40° C., the reaction was conducted by repeating block chargeof hydrogen at a gauge pressure in the range of 0 to 6 kgf/cm². Afterthe completion of the reaction, the product was analyzed through gaschromatography. Consequently, a fluorinated saturated hydrocarboncontaining 74 mol % of octafluorocyclopentane (OFCPA) and 26 mol % ofheptafluorocyclopentane (HFCPA) was obtained.

EXAMPLE 9

A flux (PO-F-1010S made by Senju Metal Industry Co., Ltd.) was coated onthe whole surface of a printed substrate (30 mm×30 mm×0.2 mm inthickness) made of a polyimide resin, and dried at room temperature.This was dipped in a detergent composition of 80 parts by weight of afluorinated saturated hydrocarbon of heptafluorocyclopentane:hexafluorocyclopentane=0:40 (molar ratio) and 20 parts by weight ofethanol at 30° C. for 3 minutes. The condition of removing the flux wasvisually observed. Consequently, it was identified that the flux wascompletely removed.

EXAMPLE 10

A product obtained by aligning 50 press-molded parts (made of stainlesssteel, 50 mm square) and bundling the same with a wire was prepared.This was dipped in a beaker containing a press oil (Tafuny Punch Oilmade by Idemitsu Kosan Co., Ltd.) at room temperature, and an ultrasonicwave was applied for 1 minute to coat the press oil throughout theproduct. The product was allowed to stand as such in the solution for 30minutes, and was then withdrawn from the press oil. The product wasallowed to stand for 5 minutes for removal of the oil. This sample wasdipped in a fluorinated saturated hydrocarbon ofheptafluorocyclopentane: hexafluorocyclopentane=80:20 (molar ratio) at50° C. for 3 minutes while applying an ultrasonic wave, and furthersteam-washed in the steam of the same fluorinated saturated hydrocarbonas mentioned above. After cooling, the removal of the oil was visuallyobserved, and the odor was confirmed. Consequently, it was identifiedthat the oil was completely removed.

EXAMPLE 11

A test for drying by draining was conducted using the same fluorinatedsaturated hydrocarbon as in Example 1.

A cover glass (15 mm×15 mm) was previously washed by degreasing. Thiswas dipped as a test piece in pure water, and then in 100 ml of thecomposition in Example 1 for 30 seconds. The test piece was withdrawn,and allowed to stand at room temperature for 1 minute for theevaporation of the residual composition.

Subsequently, it was placed in 10 g of ethanol (water content 570 ppm),and the water content increased of ethanol was measured with a KarlFischer's water content meter. Consequently, it was 30 ppm.

The increase in water content for a blank was measured using a coverglass which was allowed to stand at room temperature. Consequently, itwas 50 ppm.

Further, the increase in water content of a product which was dipped inpure water alone and not in the composition was 3,200 ppm.

In view of the foregoing, it was found that drying by draining could beconducted almost completely by using the composition of this Example.

Industrial Applicability

The invention of this application has made it possible, for the firsttime, to provide a hydrofluorocarbon (HFC), which have been known tocause no damage in the ozone layer, and to have a small global heatingcoefficient, especially a fluorinated saturated hydrocarbon containinghigh proportions of trihydrofluorocarbon, which is excellent in itschemical stability and its safety towards animals. Consequently, afluorinated saturated hydrocarbon containing, in a high proportion,trihydrofluorocarbon which can safely be used as a substitute compoundof CFC (chlorofluorocarbon) or HCFC (hydrochlorofluorocarbon) that hasfound so far wide acceptance as detergents, drain-drying agents, foamingagents, refrigerants and the like, can widely be supplied on the market.

And it goes without saying that the fluorinated hydrocarbon of theinvention of this application can be used as a detergent, a rinsedetergent, a vapor-cleaning detergent, a gap detergent or a drain-dryingdetergent.

Further, with respect to the other specific use, there are, for example,various test solvents such as solvents for testing the voltageresistance of a switch, solvents for testing ceramics polarization,solvents for testing the voltage resistance of a cathode ray tubesocket, solvent for testing the voltage resistance of a film condenserand the like; liquid mediums for rectifiers; liquid mediums fortransformers; liquid mediums for condensers; cooling heating liquidmediums for cooling in semiconductor production or cooling of a dryetching device, cooling of ozone devices, cooling of liquid crystalprojectors, cooling of power supply heat exchangers or the like;solvents for the production of a fluoropolymers; solvents for filmformation with a fluorine/silicone polymer; detergents for hollowfibers; dry cleaning solvents; solvent of a fluorine-containingelectrolytes; solvents for forming surface lubricant layer of magneticdisks or magnetic tapes; solvent for checking cracks or leak ofcastings, ceramics product or the like; chemical reaction solvents in areaction using a Lewis acid catalyst or the like; blow washing solvents;solvents for polishing disks ouch as a silicon wafer substrate, metallicsubstrate, glass substrate or the like; detergents for production ofconductor IC chips; solvent for surface treatment of a printed circuitboard; solvent for chemical mechanical polishing; photoresist solvents;developer solvents; rinse compositions; and so forth. It can also beused as medical mediums. For example, there are aerosol solvents forhuman bodies containing agents such as anti-inflammatory agents,muscular fatigue treating agents, local warming agents, analgesic orantipruritic agents, blood circulation accelerators, external agents offormulation for coating or spraying onto the human skin, inhalants,collunariums, deodorants, disinfectants, clean wiping agents or thelike; mediums for air sterilization; detergents for the sterilization ofdialysis hollow fibers; mediums for cryoperation using a catheters orcooling a medical cooler of the head or the like; polymer-containingliquids for forming polymer films on surfaces of disposal products suchas catheters, insert units, guide wires, circuits, sensors and the like,and embedding products such as artificial blood vessels, stents, anartificial bones and the like; detergents of disposal products such ascatheters, insert units, guide wires, injection needles, circuits, bags,sensors and the like, embedding products such as artificial bloodvessels, stents, artificial bones, dental members and the like, andrigid units such as forcepses, cutters (scissors), tweezers, ribspreaders and the like; pressure mediums for continuously administeringsmall. amounts of drugs to the affected portions; solvents forproduction of drug-containing gelatin capsules; solvents for coating alubricants and solvents for removing a lubricants in production ofmedical catheters; solvents for coating lubricants and solvents forremoving lubricants in artificial organs, artificial blood vessels andthe like; and so forth.

What is claimed is:
 1. A composition comprising less than 95 mol % of atrihydrofluorinated saturated hydrocarbon (A) represented by thefollowing formula (I) Rf₁—R₁—Rf₂  (I) (wherein R₁ represents a carbonchain in which CHF and CH₂ are bound, and Rf₁ and Rf₂ are bound to eachother and together represent a perfluoroalkylene chain of 2 to 4 carbonatoms, thus forming a ring with R₁) and the balance of atetrahydrofluorinated saturated hydrocarbon (B) having the same carbonnumber and the same carbon structure as said trihydrofluorinatedsaturated hydrocarbon (A), as represented by the following formula (II)Rf₁—R₂—Rf₂  (II) (wherein R₂ represents a carbon chain in which CH₂ andCH₂ are bound, and Rf₁ and Rf₂ are as defined above).
 2. The compositionof claim 1, wherein the trihydrofluorinated saturated hydrocarbon (A) isan alicyclic, fluorinated hydrocarbon having 5 carbon atoms.
 3. Thecomposition of claim 1, wherein the proportion of thetrihydrofluorinated saturated hydrocarbon (A) is 10 mol % or more. 4.The composition of claim 1, wherein the proportion of thetrihydrofluorinated saturated hydrocarbon (A) is 50 mol % or more.
 5. Aprocess for producing a composition comprising a compound represented bythe following formula (III) Rf₁—R₁—Rf₂  (III) (wherein R₁ represents acarbon chain in which CHX and CH₂ are bound, X represents a hydrogenatom or a fluorine atom, and Rf₁ and Rf₂ are bound to each other andtogether represent a perfluoroalkylene chain of 2 to 4 carbon atoms,thus forming a ring with R₁) and a compound represented by the followingformula (IV) Rf₁—R₂—Rf₂  (IV) (wherein R₂ represents a carbon chain inwhich CHX and CHF are bound, and X, Rf₁ and Rf₂ are as defined above),which consists essentially of catalytically reducing a fluorinated,unsaturated hydrocarbon represented by the following formula (V)Rf₁—R₃—Rf₂  (V) (wherein R₃ represents a carbon chain of —CX═CF—, Xrepresents a hydrogen atom or a fluorine atom, and Rf₁ and Rf₂ are boundto each other and together represent a perfluoroalkylene chain of 2 to 4carbon atoms, thus forming a ring with R₁) under hydrogen using a noblemetal catalyst, and controlling the proportions of the fluorinatedsaturated hydrocarbon of formula (III) and the fluorinated saturatedhydrocarbon of formula (IV) by changing the polarity of the componentother than the substrate starting material of the reaction system. 6.The process for producing a composition of claim 5, wherein thefluorinated saturated hydrocarbon of formula (III) is selectivelyproduced through catalytic reduction by making the component other thanthe substrate starting material of the reaction system to have a highpolarity.
 7. The process for producing a composition of claim 6, whereinthe catalytic reduction is conducted using a starting material in whichthe proportion of the high-polarity compound in impurities is increasedby containing the high-polarity compound in the fluorinated, unsaturatedhydrocarbon represented by formula (V) as the substrate startingmaterial or by removing a low-polarity compound from among impuritiesaccompanying the substrate starting material.
 8. The process forproducing a composition of claim 5, wherein the fluorinated saturatedhydrocarbon of formula (IV) is selectively produced through catalyticreduction by making the component other than the substrate startingmaterial of the reaction system to have a low polarity.
 9. The processfor producing a composition of claim 8, wherein the catalytic reductionis conducted using a starting material in which the proportion of thelow-polarity compound in impurities is increased by containing thelow-polarity compound in the fluorinated, unsaturated hydrocarbonrepresented by formula (V) as the substrate starting material or byremoving the high-polarity compound from among impurities accompanyingthe substrate starting material.
 10. The process for producing acomposition of claim 7, wherein the low-polarity compound is containedin the starting material in an amount of 0.5% by weight or less, or thehigh-polarity compound is contained in the starting material in anamount in the range of 0.1 to 15% by weight.
 11. The process forproducing a composition of claim 9, wherein the high-polarity compoundis contained in the starting material in an amount of 0.5% by weight orless, or the low-polarity compound is contained in the starting materialin an amount in the range of 0.1 to 15% by weight.
 12. The process forproducing a composition of claim 7 or 9, wherein the low-polaritycompound is selected from the group consisting of paraffins, naphthenesand aromatics, and the high-polarity compound is selected from the groupconsisting of alcohols, polyhydric alcohols, polyhydric alcoholmonoethers, amides and sulfoxides.
 13. The process for producing acomposition of claim 6, wherein a trihydrofluorinated saturatedhydrocarbon of formula (III) is selectively produced by using afluorinated, unsaturated hydrocarbon having a carbon chain of —F═CF— inwhich the symbol X in formula (V) represents a fluorine atom as astarting material.
 14. The process for producing a composition of claim8, wherein a trihydrofluorinated saturated hydrocarbon of formula (IV)is selectively produced by using a fluorinated, unsaturated hydrocarbonhaving a carbon chain of —CH═CF— in which the symbol X in formula (V)represents a hydrogen atom as a starting material.
 15. The process forproducing a composition of claim 6 or 8, wherein formula (V) of thestarting material is an alicyclic fluorinated, unsaturated hydrocarbonhaving 5 carbon atoms.
 16. The process for producing a composition ofclaim 5, wherein the noble metal is palladium, rhodium, ruthenium,rhenium or platinum.
 17. The process for producing a composition ofclaim 5, wherein the catalytic reduction is conducted as a liquid phasereaction or a gaseous phase reaction at a temperature in the range ofroom temperature to 350° C. under hydrogen of a pressure in the range ofatmospheric pressure to 10 kg/cm².
 18. The composition of any one ofclaim 1, 2, or 4, further comprising at least one type of an organicsolvent having a boiling point of at least 25° C. and at most 250° C.19. The composition of claim 18, wherein the amount of the organicsolvent having the boiling point of at least 25° C. and at most 250° C.is 50% by weight or less based on the total amount.
 20. The compositionof claim 19, wherein the amount of the organic solvent is between 2 and30% by weight based on the total amount.
 21. The composition of claim19, wherein the organic solvent is selected from the group consisting ofhydrocarbons, alcohols, esters, chlorinated hydrocarbons, fluorinatedhydrocarbons, ethers, ketones and volatile organosilicones.